A clinical study was conducted from May to July 2017 in the outpatient department of Bandaranaike Memorial Ayurvedic Research Institute (BMARI), Navinna, Sri Lanka to test the antitumor activity of the indigenous drug modality which is used to manage the colon cancer. A forty year old colon cancer patient volunteered to the study. Ethical approval has been taken from the Institute of Indigenous Medicine, University of Colombo Sri Lanka. Detailed history, clinical examinations and relevant investigations were conducted at BMARI and the Department of Zoology, Faculty of Science, University of Ruhuna. Three herbal formulations namely SG powder- 5g/day, KY powder -10g/day and A1 powder -10g/day were given for the patient throughout 90 days of study. Serum Interleukin-2 (IL-2), Interleukin-5 (IL-5), Interleukin 17 (IL-17), Interferon (IFN)-ɣ and p53 Upregulated Modulator of Apoptosis (PUMA) were quantified using Enzyme-Linked Immunosorbent Assay (ELISA) before and after the treatments (after 45 and 90 days) as these cytokines play a significant role in tumor growth control. Tumor marker expression and stool samples were tested before and after treatments (after 45 and 90 days). Symptoms of colon cancer were significantly decreased during the treatment along with changes in tumor markers. According to the results of the ELISA, IL-2, IFN-ɣ and IL-17 concentrations were increased significantly after the treatment and expression level increased in all three cytokines over time indicating the possible control of colon cancer growth by the drug modality. Further investigations are required to evaluate the mechanism of effectiveness of this indigenous drug modality in controlling carcinoma of colon.